Apparatus and method for detection and mitigation of conditions that are favorable for transmission of respiratory diseases

ABSTRACT

Systems and methods are provided for detecting a potential for dewpoint respiratory inoculation (DRI). A method includes detecting a change in temperature over time, determining a slope of the change in temperature, comparing the slope of change in temperature with a slope threshold, and if the slope of change in temperature exceeds the slope threshold, then signaling a potential for dewpoint respiratory inoculation. Detection systems can include a personal device with temperature and humidity detectors, a processor for collecting data and identifying conditions that may provoke DRI, and providing a signal to the user.

RELATED CASES

This application claims the benefit of Provisional Patent ApplicationSerial No. 63/050,875, filed Jul. 13, 2020.

BACKGROUND Field of the Invention

The present disclosure relates generally to systems and processes fordetecting transient conditions of increased danger of respiratorydisease infection, and more particularly, to detection of conditions inwhich the likelihood of condensation of water from ambient air onto thelinings of a subject’s airways is increased.

Related Art

The human body has a very effective, tiered system for preventing harmdue infection, parasites, harmful chemicals, environmental factors,etc., and for regulating normal body function under varyingenvironmental conditions. For example, the immune system is acell-mediated system that works to combat and eliminate pathogens thatmay have entered the body, to prevent or minimize damage that mightotherwise occur. However, there are a number of processes, structures,and elements that work to prevent the entry of these harmful substancesand pathogens into the body in the first place. Included in this groupare various mucous membranes—mucosa—including membranes that line thenasal passages, sinuses, mouth, throat, trachea, and bronchioles of thelungs, which secrete a layer of mucous. This mucous traps foreignmatter, such as pathogens, pollen, dust, etc., which would otherwise beinhaled into the lungs, while acting as a barrier, to preventingpathogens, in particular, from contacting the mucosa directly Mucousalso has antiseptic/antimicrobial properties to combat pathogens in theairways. Additionally, inhaled air is warmed and humidified by contactwith mucous, so that, ideally, by the time it reaches the lungs it hasbeen warmed to within a few degrees of normal body temperature and isnear 100% relative humidity.

When the condition of the air changes, the body responds by modifyingthe production of mucous in order to maintain a constant supply ofclean, warm, and humid air. For example, if the ambient temperaturedrops, the body’s production of mucous will increase. This serves twopurposes: First, colder air requires more thermal energy to bring it tobody temperature than warm air, and the larger volume of mucous carriesmore thermal energy into the nasal passages to accomplish this. Andsecond, as air temperature increases, its relative humidity drops, andit becomes drier. The increase in mucous production provides additionalmoisture to properly humidify the air.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are charts showing the water content per liter of air atvarious temperatures, and the corresponding relative humidity at thosetemperatures.

FIG. 2 is a block diagram of a Dewpoint Respiratory Inoculation (DRI)detector, according to an embodiment, which is configured to be carriedby a user, to monitor the ambient environment, and to warn the user whenconditions may provoke DRI.

FIG. 3 is a flow chart showing a process for detecting conditions thathave the potential of provoking DRI, according to an embodiment.

FIG. 4 is a diagrammatic side view showing an example of a system forprotecting individuals from DRI as they enter and exit a building,according to an embodiment.

DETAILED DESCRIPTION

There is a well-recognized statistical relationship between seasonalchanges in temperature and humidity and the incidence of respiratoryillnesses, such as, e.g., influenza and coronaviruses. The particularmechanism(s) responsible for the correlation are not well understood. Inparticular, there appears to be a stronger correlation betweenconditions in which individuals are subjected to artificially controlledenvironments and the incidence of infections than those in which thevariations in temperature and humidity occur naturally. In other words,people who work primarily outdoors and/or live and work in environmentsthat are not strongly temperature regulated year around arestatistically less susceptible to various kinds of infections thanpeople who live and/or work in spaces that are highly regulated by HVACsystems. This is puzzling because, on the one hand, there is arecognized correlation between seasonal variations and the incidence ofrespiratory infections, while on the other hand, those people who arethe least exposed to such variations, i.e., those who spend much oftheir time in climate-controlled conditions, appear to be the mostsusceptible to infection.

Many theories have been proposed to explain these and related issues,but the available answers have so far not been fully satisfactory. Theinventor believes that the significance of these correlations has notbeen fully understood by previous theorists, and that a significantcontributing factor to these phenomena is Dewpoint RespiratoryInoculation (DRI), as explained below.

It is widely understood that airborne pathogens are frequently carriedon small water droplets that are exhaled by contagious individuals. In adry environment, the droplets quickly evaporate and become gaseous, sothat the pathogens—and other vapor-borne contaminants—are no longersupported and fall out of the air. However, in a relatively humidenvironment water droplets can be quite persistent, the smallest ofwhich can remain in the air for many minutes after being exhaled by acontagious individual. One of the functions of mucous in the airway isto capture these droplets, which can be transported away from the lungsby processes such as ciliary action, then removed from the airway viacoughing, sneezing, swallowing, etc.

As noted above, the human body is able to regulate the production ofmucous in response to changes in temperature and humidity. However, theinventor has recognized that such regulation is not unlimited incapacity, nor is it instantaneous. First, even though the rate of mucousproduction is variable, an individual’s airway can become generallydrier in very dry conditions. Second, as the individual inhales andexhales, the conditions in the airway fluctuate in response to the airpassing through. When cold, dry air is inhaled, the air does not becomeinstantly warm and humid, but instead is progressively conditioned alongthe length of the airway, and will dry and chill the mucous andmembranes in the nasal passages as it becomes warmer and more humid.

The process is reversed as the individual exhales warm, moist air acrossthe depleted membranes, so that the drying and chilling effect isrepeated with each breath. This will occur, in particular, in thoseportions of the nasal passages first encountered as the air enters thepassages, but can extend the length of the airway and even into thelungs, depending upon the ambient conditions and volume of the inflowingair (a person who is breathing hard will inhale and exhale a highervolume of air per unit of time). Under more extreme conditions, agreater length of the airway will be chilled and dried by the air. Ifthe air is relatively cold, this will occur regardless of the relativehumidity of the air, because as even very humid cold air is warmed, itsrelative humidity plummets, and it becomes relatively very dry. However,even warm air can produce the same effect if it is very dry: rapidevaporation of moisture in the mucous, as will happen if the air isextremely dry, will cause the temperature of the mucous and mucosa todrop. This drying and chilling effect leaves the mucosa less protectedfrom pathogens in the air. Drying and thickening of the mucous caninhibit mucociliary function, and pathogens that settle on depleted(partially dehydrated) mucous or directly on an exposed surface of amucous membrane are less likely to be encapsulated by mucous that isformed thereafter, but may instead establish a colony, so that theindividual becomes infected by the pathogen.

FIGS. 1A and 1B are charts showing the water content per liter of air atvarious temperatures, and the corresponding relative humidity at thosetemperatures. The dew point corresponds to the 100% humidity line. Ifair that is fully saturated—i.e., at 100% humidity-drops in temperature,sufficient water will precipitate from the air onto nearby surfaces sothat the relative humidity stays at or below 100% relative humidity.Thus, if the outside temperature is 32° C. (about 90° F.) with 80%humidity, the air will reach saturation—i.e., 100% relative humidity—ifcooled to around 28° C. (about 82° F.), and further cooling will causewater to precipitate. If this occurs in nasal passages that have beendried and chilled by a period of exposure to cool or cold, dry air, andif the first moisture that reaches the surfaces of those passages isladen with pathogens, the individual risks inoculation by one or anotherof the pathogens. Hence, Dewpoint Respiratory Inoculation.

The inventor has recognized that this vulnerability is most acute in themoments after an individual passes into a humid environment but beforethe mucosa in the nasal passages recovers from the previously dryconditions. If the ambient air changes very quickly from cold and dry towarm and humid, warm air entering the nasal passages will actually beinitially chilled, as it enters the nasal passages, by contact with thesurfaces that had been previously cooled by the colder environment. Thischilling can cause the incoming humid air to drop below its dew pointtemperature, so that humidity from the air precipitates to water on thesurfaces of the nasal passages before mucous can be reformed. This canhappen, for example, when an individual leaves an airconditionedbuilding on a hot, humid, summer day, as shown by the arrow in FIG. 1A,or when the individual enters a heated building on a cold winter day asshown by the arrow in FIG. 1B. The mucous membranes are momentarilymoistened by precipitating water vapor rather than mucous, so thatpathogens deposited there by microdroplets in the air may find an idealsurface for establishing a colony.

Thus, the inventor believes that the point of greatest danger ofinfection occurs in what might be referred to as a critical transitionzone (CTZ) that can be present between an artificially controlledenvironment and the surrounding natural environment, in which thedifferences in temperature and humidity are sufficient to provoke DRI,as an individual moves from a cool or cold environment to a warm or hotenvironment, particularly when humidity in the warmer environment isrelatively high.

The period during which the body is most vulnerable as it adjusts to thenew environment may be only a few seconds or may last longer, dependingupon factors such as the magnitude of the transition in temperature, thehumidity of the warmer environment, and the length of time spent by theindividual in the colder environment, during which the individual’snasal passages may become progressively drier. Individuals who spendmost of their time in climate-controlled environments may cross throughmany CTZs over the course of a day, as they transition from home tovehicle to work, etc. At each transition, these individuals aresubjected to a short period during which their natural defenses may becompromised.

This is in contrast to situations in which individuals may live in homesthat are not airconditioned, and/or work outdoors or in facilities thatare not airconditioned. In these circumstances, the transitions areusually fewer, less abrupt, and of lower magnitudes, producingconditions that are less likely to provoke DRI.

The inventor also believes that drinking a cold beverage in a warm andhumid environment can also provoke DRI, as the cold liquid chills thethroat and nasal passages, after which warm air inhaled by theindividual may be chilled to its dewpoint in the individual’s throat ornasal passages.

The inventor is not aware of any previous work evaluating the effect,specifically, of these transition zones on the susceptibility of anindividual to airborne pathogens. The inventor proposes a number ofsystems and processes that address this problem in various ways,according to respective embodiments.

A first step in protecting an individual from DRI is notification. If aperson is aware of the possibility of DRI in a particular situation, shemay be able to take measures to mitigate the danger of infection.Therefore, according to an embodiment, a device is provided that isconfigured to detect abrupt changes in temperature and humidity, andwarn the user of a temperature change of sufficient amplitude andsufficiently short duration as to potentially provoke DRI. Embodimentsare also contemplated that provide various responses to conditions inwhich DRI is a potential problem.

FIG. 2 is a block diagram of a DRI detector 100 that is carried by auser and configured to monitor the ambient environment, and to warn theuser when conditions may provoke DRI, according to an embodiment. Thedetector 100 includes a case 102 that can be worn outside the user’sclothing on a cord or chain, or that can be clipped to the user’sclothing-but away from where it might be influenced by the user’s ownbreath. Mounted to the case 102 are a temperature sensor 104, a humiditysensor 106, a signal lamp 108 and a signal speaker 110. Within the case,a signal conditioning module 112 is configured to receive signals fromthe temperature and humidity sensors 104, 106, and to output aconditioned signal for each to a logic module 114. A clock 116 is alsoconfigured to provide a timing signal to the logic module 114, and amemory 118 is configured to store data and timing information used bythe logic module. An alarm module 120 is configured to provide alerts tothe user, and a wireless transceiver module 122, such as, e.g., aBluetooth module, is configured to communicate with another device, suchas a user’s smartphone, etc. A battery 124 is configured to providepower to each of the components of the DRI detector 100. The logicmodule 114 is configured to receive the conditioned signals from thesignal conditioning module 112 and the timing signal from the clock 116,and, on the basis of changes in the values of the conditioned signalsover time, detect conditions that could provoke DRI. The alarm module120 is configured to receive an alarm command from the logic circuit 114and to provide a visual and/or audible alarm signal via the signal lamp108 or the signal speaker, or via the wireless module 122, dependingupon preference settings and configuration of the device.

According to one embodiment, the system shown in FIG. 2 employs adigital circuit. According to another embodiment, an analogue circuit isused, which, may include, for example, an integrator circuit to detectthe slope of the incoming temperature signal, the charge constant of acapacitor and resistor to define the slope threshold, and a comparatorto detect conditions that exceed the threshold.

Various embodiments are envisioned that include different combinationsof the elements shown and described with reference to FIG. 2 . Forexample, according to one embodiment, the wireless module 122 isomitted, and all functions are performed by components within the case102. In another embodiment, the humidity sensor 104 is omitted, and thedevice is configured to detect a potential DRI based on temperaturechanges, alone.

According to a further embodiment, a separate device is provided, e.g.,a smartphone or other personal digital device, which is configured toperform the functions of many of the modules shown in FIG. 2 , such asthe logic module 114, the memory 118, and the signal module 120, as wellas the signal output components, i.e., the signal lamp 108 and thesignal speaker 110. Accordingly, these elements are omitted as physicalcomponents within the case 102 of the DRI detector 100. In thisembodiment, the components within the case 102 provide sensor functionswhile the separate device provides processor functions.

In the description of the embodiment of FIG. 2 , various components andmodules are described as separate elements, for clarity of description.However, in other embodiments these elements are combined into fewerelements or separated into more elements that nevertheless perform thedefined functions. Furthermore, in some embodiments elements aredistributed among multiple devices that cooperate to perform thenecessary functions. Furthermore, those multiple device may also beconfigured to perform other, unrelated functions in addition to thosedescribed here. To the extent that a system includes a structure orcombination of structures that perform all of the functions recited in aclaim, the claim reads on that system, at least with respect to thosefunctions, even if the structures of the system cannot be easilyseparated into individual devices, each performing exactly the functionsof a corresponding device or module recited in the claim. Likewise, asystem that includes a processor configured to execute softwareinstructions, in combination with such structures as would be necessaryto perform the recited functions, and a memory device in whichinstructions for the performance of the recited functions are stored, isalso within the scope of such a claim.

In operation, the DRI detector 100 is configured to detect conditionsthat have the potential of provoking DRI and to notify the user, asdescribed, according to one embodiment, below with reference to FIG. 3 .Once notified, the user can then take measures to mitigate the danger. Asimple response may be for the user to take note of locations where thedetector 100 commonly triggers an alert, and thereafter, just prior topassing through such locations, to use an inhaler or mister tomoisturize the user’s airways prior to inhaling air that may potentiallyinclude dangerous pathogens.

According to an embodiment, a mask is provided that includes a mister,which is coupled to automatically release a burst of moist air uponreceipt of an alert signal from a device such as the detector 100 ofFIG. 2 .

FIG. 3 is a flow chart showing a process 130 for detecting conditionsthat have the potential of provoking DRI, according to an embodiment.The process 130 can be performed by the DRI detector 100 of FIG. 2 , andwill be described in that context. However, there are many other typesand configurations of devices that can also perform or be configured toperform the process 100. The claims are therefore not limited to thedevice described above or elsewhere in the present disclosure.

The process 130 is initiated, at step 132, by the user turning thedevice on or entering a start command, etc. The ambient temperature andhumidity are detected and saved in step 134. The temperature andhumidity are again detected, in step 136, and saved. According to anembodiment, step 136 is performed a selected time period afterperformance of step 134, or in the case of a repetition of step 136, therepetition is performed the same selected time period after the previousiteration of the step. According to another embodiment, the detectionstep 136, and repeats thereof, are performed and the elapsed timebetween detection steps is also saved.

In step 138, the a previously detected temperature is subtracted fromthe most recently detected temperature to obtain an amplitude of change.The slope of change is calculated, in step 140. The term amplituderefers to a difference in temperature from one iteration of a detectionstep 134, 136 to a succeeding iteration. The term slope refers to thedegree of change in temperature over the time elapsed between thedetection steps in which the change occurred. For example, a change intemperature of ten degrees within a period of two seconds will have asteeper slop than a change of five degrees over the same period.

In step 142, the slope and amplitude are compared with respectivethresholds and a determination is made whether the slope and amplitudeboth exceed respective thresholds. If either value does not exceed itsthreshold, the process returns to step 136 and repeats from that point.If, however, both thresholds are exceeded, the humidity is compared witha threshold, in step 144, and a determination is made whether thehumidity exceeds its threshold. If not, the process again returns tostep 136 and repeats from that point. However, if the humidity exceedsits threshold, then in step 146, an alarm signal is sent, indicatingthat the conditions for potential DRI are present. The process thenreturns to step 136 and repeats from that point. There are a number offactors that can affect the likelihood of DRI, and therefore may beconsidered in determining the values of the various thresholds. Forexample, if the user moves from a warm environment to a coolerenvironment, but only remains for a short time before moving back to awarm environment, the user’s nasal passages will not have dried as muchas they would have after a longer period. Thus, according to anembodiment, the slope and/or amplitude thresholds are gradually reducedfrom initially higher values as the user remains in the coolerenvironment, so that a greater and/or faster change in temperature isinitially required to trigger the alarm signal, but over time thethresholds are reduced. The various detected and calculated values canalso influence the thresholds of the other values. For example, if therelative humidity is very high, it would not require as great a changein temperature, or as abrupt, to force precipitation in the nasalpassages, and, conversely, if the change in temperature is very greatand/or very fast, precipitation will occur even with a much lowerrelative humidity. Therefore, according to an embodiment, each thresholdis configured to vary in response to changes in the other values.

According to another embodiment, only the humidity threshold isadjusted. In the process described with reference to FIG. 3 , humidityis compared with its threshold only after the slope and amplitude of thetemperature have been determined and compared with their respectivethresholds. Therefore, the temperature slope and amplitude thresholdsare fixed at a conservative level so that a “YES” value is obtainedunder any likely conditions. The humidity threshold is then set suchthat an alarm signal will be produced only if the conditions areactually appropriate.

As noted above, when cold air is warmed, it will become very dry,regardless of its previous degree of humidity. Additionally, mosttemperate climates include sufficient humidity to reach the dew pointwith only modest chilling. For example, as can be seen in the chart ofFIGS. 1 , air at a temperature of 95° F. (about 95° C.) with a relativehumidity of 50% will reach 100% humidity if chilled to around 75° F.(about 24° C.). Thus, according to a further embodiment, a process isprovided in which only the temperature is measured and compared.

According to an embodiment, algorithms are provided for the calculationsperformed in step 140 and the selection of the thresholds used in steps142 and 144. According to an alternative embodiment, lookup tables areprovided to determine one or more of the temperature slope, and thethresholds for the slope, amplitude, and humidity.

According to an embodiment, a device is provided that is configured tomitigate the danger by providing a clean or sterile humidifying vapor ormist that serves to moisturize the nasal passages without inoculatingthem with a harmful pathogen. The device is configured to detect thepassage of the individual into a CTZ, and respond by outputting a briefflow of vapor during the most vulnerable seconds of transition.

According to another embodiment, a device is provided that is configuredto operate in the entrance vestibule of an air conditioned and/or heatedbuilding, in which one or more technologies are used to create a safertransition zone between the temperature and humidity extremes of theinterior and exterior. This can include maintaining a temperature in thevestibule that is between the higher and lower temperatures, so that aperson passing through the vestibule does not experience a singleextreme temperature transition, but instead two smaller temperaturetransitions, neither of which is sufficient to provoke DRI. According toanother embodiment, an air curtain is provided within the vestibule thatcreates a flow of clean humid air to remoisturize the nasal passages andother airways with clean moisture before the individual is exposed toair that may be laden with harmful pathogens.

FIG. 4 is a diagrammatic side view showing an example of a system 160for protecting individuals from DRI as they enter and exit a building,according to an embodiment. The system 160 includes a building vestibule162 with doors 164 through which individuals pass to enter and exit abuilding. The system 160 also includes a portion of the building HVACsystem 168 that is configured to modify the environment within thevestibule. The controller 166 receives data from temperature andhumidity sensors 104, 106 positioned inside and outside the building,and processes the data to detect conditions in which DRI is a potentialdanger, as described in more detail above. Under such conditions, thecontroller 166 signals to the HVAC system 168 which regulates thetemperature within the vestibule 162 to be between the temperaturesinside and outside the building. As people enter and exit the building,and breathe the air in the vestibule, their airways are transitionedmore gradually from the extremes of temperature outside the vestibule sothat the risk if DRI is reduced or eliminated.

In various of the processes described in the present disclosure, one ormore parameters are detected, measured, or determined. As used in thespecification and claims, terms such as detect, measure, determine,compare, etc. are not limited to actually obtaining a numerical valuefor such parameters. For example, the process described with referenceto FIG. 3 includes repeated steps of detecting a temperature, at steps134, 136, obtaining a difference amplitude between the detectedtemperatures at step 138, and, in step 142, comparing the amplitude witha threshold temperature. While some control systems may be configured toprovide actual temperature values, calculate the difference, and thencompare the results with a threshold value, there are many alternativesolutions that are acceptable; obtaining the actual temperature value,e.g., in degrees Fahrenheit or degrees Celsius, may not be necessary.

For example, according to an embodiment, the temperature sensor is atransducer configured to provide a voltage signal that varies directlyor inversely with variations in temperature. A voltage representing afirst temperature reading is captured by a first sample and hold (SH)circuit. A voltage representing a second temperature reading is thencaptured by a second SH circuit and the captured values from the firstand second SH circuits is outputted to a differencing circuit, whichproduces an output voltage that corresponds to the amplitude of adifference between its two inputs. The temperature amplitude thresholdis represented by a corresponding reference voltage, and the comparisonof the amplitude with the temperature threshold is performed by acomparator circuit coupled to receive the voltage signal from thedifferencing circuit at a first input and the reference voltage at asecond input. The comparator circuit is configured to produce one of twobinary values, depending upon which of the two voltage signals isgreater, and the resulting binary value indicates whether the amplitudeis greater than the threshold, or vice versa.

In the embodiment described above, the numerical values of the actualtemperatures are not measured, or determined, in a narrow sense of theterm, nor are such values used to calculate the amplitude of change, noris a numerical value representing the amplitude compared with anumerical value representing the amplitude threshold. Instead, voltagesignals that are representative of the actual temperatures are processedto produce another voltage signal that is compared with a voltage signalrepresentative of the threshold value, with the necessary determinationbeing made on the basis of that comparison. Nevertheless, where such aconfiguration is adequate to make the necessary determination, it isconsidered to perform the corresponding steps, and would thus fallwithin the scope of a claim that included a term such as detect,measure, subtract, determine, compare, etc., in referring to such anoperation or structure.

Accordingly, claim language referring to or reciting operationsinvolving physical parameters, such as pressure, temperature, humidity,time, rate, power, etc., includes within its scope processes or processsteps in which representative or inferred values are manipulated, using,for example, analog or digital circuits, the execution of softwareinstructions, lookup tables, etc., to arrive at a corresponding outcome,even if the actual physical parameters are not employed in the process,and/or are never actually derived.

The inventor has prepared a white paper outlining elements of hisinvention and the underlying principles, which is submitted via anaccompanying information disclosure statement, and which is incorporatedherein by reference, in its entirety.The abstract of the presentdisclosure is provided as a brief outline of some of the principles ofthe invention according to one embodiment, but is not intended as acomplete or definitive description of any single embodiment thereof, norshould it be relied upon to define terms used in the specification orclaims. The abstract does not limit the scope of the claims.

It will be understood that the scope of the appended claims should notbe limited by particular embodiments set forth herein, but should beconstrued in a manner consistent with the specification as a whole.

What is claimed is:
 1. A process for detecting a potential for dewpointrespiratory inoculation (DRI), comprising: detecting a change intemperature over time; determining a slope of change in temperature;comparing the slope of change in temperature with a slope threshold; andif the slope of change in temperature exceeds the slope threshold, thensignaling a potential for dewpoint respiratory inoculation.
 2. Theprocess of claim 1, wherein the detecting a change in temperature overtime comprises: detecting a first temperature; after detecting the firsttemperature, detecting a second temperature; defining a length of timebetween detecting the first temperature and detecting the secondtemperature.
 3. The process of claim 2, wherein: the detecting a secondtemperature comprises detecting a second temperature after a selectedperiod of time following the detecting a first temperature; and thelength of time between detecting the first temperature and detecting thesecond temperature is equal to the selected period of time.
 4. Theprocess of claim 2, wherein: the defining a length of time betweendetecting the first temperature and detecting the second temperaturecomprises measuring an elapsed time between detecting the firsttemperature and detecting the second temperature.
 5. The process ofclaim 2, comprising: selecting the slope threshold based on one of thefirst or second temperatures.
 6. The process of claim 1, wherein thesignaling a potential for dewpoint respiratory inoculation comprisesproducing an audible signal.
 7. The process of claim 1, wherein thesignaling a potential for dewpoint respiratory inoculation comprisesproducing a visible signal.
 8. The process of claim 1, comprising:detecting a relative humidity; comparing the detected relative humiditywith a humidity threshold; and wherein the signaling a potential fordewpoint respiratory inoculation includes: if the slope of change intemperature exceeds the slope threshold, and if the detected relativehumidity exceeds the humidity threshold, then signaling a potential fordewpoint respiratory inoculation.
 9. The process of claim 1, comprising:detecting a relative humidity; and selecting the slope threshold basedon the detected relative humidity.
 10. A system for detecting apotential for dewpoint respiratory inoculation (DRI), comprising: atemperature detection module configured to detect an ambienttemperature; a clock module; and a processor module configured to:compare a first temperature detected at a first time with a secondtemperature detected at second time, after the first time, determine aslope of temperature change over time, compare the slope of temperaturechange over time with a slope threshold, and signal a potential for DRIif the slope of temperature change over time exceeds the slopethreshold.
 11. The system of claim 10, comprising: a memory moduleconfigured to store the first temperature and the first time.
 12. Thesystem of claim 10, comprising: a humidity detection module configuredto detect an ambient humidity.
 13. The system of claim 10, comprising awireless communication module configured to provide communicationbetween a sensor component and a processor component of the system. 14.The system of claim 13, wherein the sensor component includes thetemperature detection module and the processor component includes theprocessor module.
 15. The system of claim 14, wherein the processorcomponent is a personal digital device configured to be carried by auser.
 16. The system of claim 15, wherein the personal digital deviceincludes a nonvolatile memory containing instructions that areexecutable by the personal digital device to perform the functions ofthe processor module.